3x^2-4x=20-15x

Solution for 3x^2-4x=20-15x equation:

3x^2-4x=20-15x

We move all terms to the left:

3x^2-4x-(20-15x)=0

We add all the numbers together, and all the variables

3x^2-4x-(-15x+20)=0

We get rid of parentheses

3x^2-4x+15x-20=0

We add all the numbers together, and all the variables

3x^2+11x-20=0

a = 3; b = 11; c = -20;
Δ = b2-4ac
Δ = 112-4·3·(-20)
Δ = 361
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{361}=19$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(11)-19}{2*3}=\frac{-30}{6}
=-5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(11)+19}{2*3}=\frac{8}{6}
=1+1/3
$